Process for the catalytic synthesis of biaryls and polymers from aryl compounds

ABSTRACT

A process for producing organic substituted aromatic or heteroaromatic compounds including biaryl and biheteroaryl compounds in a two-step reaction. In the first step, the aromatic or heteroaromatic compound is borylated in a reaction comprising a borane or diborane reagent (any boron reagent where the boron reagent contains a B—H, B—B or B—Si bond) and an iridium or rhodium catalytic complex. In the second step, a metal catalyst catalyzes the formation of the organic substituted aromatic or heteroaromatic compound from the borylated compound and an electrophile such as an aryl or organic halide, triflate (OSO 2 CF 3 ), or nonaflate (OSO 2 C 4 F 9 ). The steps in the process can be performed in a single reaction vessel or in separate reaction vessels. The present invention also provides a process for synthesis of complex polyphenylenes starting from halogenated aromatic compounds.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to Provisional Application No.60/305,107, filed Jul. 13, 2001, and to Provisional Application No.60/332,092, filed Nov. 21, 2001.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] This invention was supported in part by National Institutes ofHealth, National Institute of General Medical Sciences Grant No. R01GM63188-01 and in part by National Science Foundation Grant No.CHE-9817230. The U.S. government has certain rights in this invention.

REFERENCE TO A “COMPUTER LISTING APPENDIX SUBMITTED ON A COMPACT DISC”

[0003] Not Applicable.

BACKGROUND OF THE INVENTION

[0004] (1) Field of the Invention

[0005] The present invention relates to a process for producing organicsubstituted aromatic or heteroaromatic compounds including biaryl andbiheteroaryl compounds in a two-step reaction. In the first step, thearomatic or heteroaromatic compound is borylated in a reactioncomprising a borane or diborane reagent (any boron reagent where theboron reagent contains a B—H, B—B or B—Si bond) and an iridium orrhodium catalytic complex. In the second step, a metal catalystcatalyzes the formation of the organic substituted aromatic orheteroaromatic compound from the borylated compound and an electrophilesuch as an organic or aryl halide, triflate (OSO₂CF₃), or nonaflate(OSO₂C₄F₉). The steps in the process can be performed in a singlereaction vessel or in separate reaction vessels. The present inventionalso provides a process for synthesis of complex polyphenylenes startingfrom halogenated aromatic compounds.

[0006] (2) Description of Related Art

[0007] Carbon-carbon bonds are the molecular “bricks and mortar” fromwhich diverse architectures in living organisms and man-made materialsare constructed. As the field of organic chemistry has evolved, numerousmethods for carbon-carbon bond construction have been developed, rangingfrom classic examples, like the Diels-Alder reaction, to more recentmetal-catalyzed processes such as olefin polymerizations and metatheses.

[0008] Substituted aromatic, and their heteroaromatic analogs, areabundant in natural and in synthetic materials. Consequently, controlledmethods for linking aromatic rings via C—C sigma bonds have long beenpursued by organic chemists. Activity in this regard intensified in thelate 1970's during which Pd catalyzed methods for C—C bond constructionemerged (Diederich and Stang, Metal-Catalyzed Cross-Coupling Reactions.Wiley-VCH, New York (1998)). Notably, the Pd catalyzed coupling of anarylboronic acid and an aryl halide disclosed by Miyaura and Suzuki,

[0009] (Y=OH; X=halide) has become a method of choice for preparingbiaryls since it is performed under mild conditions, tolerant of diversefunctionality, and highly selective (Miyaura et al., Synth. Commun. 11:513-519 (1981)). Subsequent developments in metal-catalyzedcross-couplings of organoboron compounds and organic halides haveyielded practical C—C bond forming strategies that complement existingmethodology (Suzuki, Organomet. Chem. 576 ; 147-168 (1999)). Today theMiyaura-Suzuki reaction is routinely applied in high-throughputscreening for drug discovery (Sammelson and Kurth, Chem. Rev. 101:137-202 (2001)), in the final steps of convergent natural productsyntheses (Chemler and Danishefsky, Org. Lett. 2: 2695-2698 (2000)), andin the synthesis of conjugated organic materials (Schlütter, J. Polym.Sci. A-Polym. Chem. 39: 1533-1556 (2001)).

[0010] Arylboron reagents are typically synthesized in a multi-stepprocess such as that shown below.

[0011] Shorter routes that avoid undesirable halogenated aromaticintermediates would be attractive. Towards this end, theoreticalestimates of B—H and B—C bond enthalpies gave credence to organoboranesynthesis via the thermal dehydrogenative coupling of B—H and C—H bondsas shown below (Rablen et al., J. Am. Chem. Soc. 116: 4121-4122 (1994)).

[0012] Some key steps in putative catalytic cycles for this process hadbeen established with Hartwig's (Waltz et al., J. Am. Chem. Soc. 117:11357-11358 (1995); Waltz and Hartwig, Science 277: 211-213 (1997)) andMarder's reports of stoichiometric borylations of arenes, alkenes, andalkanes by metal boryl complexes (M-BR₂). Although arene activationproducts were not mentioned, small peaks in the GC-MS trace with massesconsistent with toluene borylation products were assigned in theSupplementary Material to Nguyen et al., Am. Chem. Soc. 115,9329-9330(1993).

[0013] While Hartwig has developed elegant photochemical methods forhydrocarbon borylation using catalytic amounts of metal complexes (Chenand Hartwig, Angew. Chem. Int. Ed. 38: 3391-3393 (1999)), thermal,catalytic borylations of unactivated hydrocarbons had not beendocumented prior to our report in 1999 (Iverson and Smith, III, J. Am.Chem. Soc. 121: 7696-7697 (1999)). Since then, borylation of aliphaticand alkyl branched alicyclic hydrocarbons at a primary C—H hydrocarbonbond under thermal conditions using a rhodium catalytic complex whichincludes an electron donor ligand was disclosed in WO 01/64689 A1 andU.S. patent application Ser. No. 0039349 A1, both to Chen et al., andborylation of cyclic hydrocarbons at a secondary or aromatic C—H cyclichydrocarbon bond using the above rhodium catalytic complex was disclosedin WO 01/64688 Al to Chen et al.

[0014] Currently, because C—C coupling of a hydrocarbon requires amulti-step process to produce a borylated hydrocarbon, which is thenreacted with a hydrocarbon halide to couple the hydrocarbons, it wouldbe desirable to have a process wherein the borylation and the C—Ccoupling are performed in fewer steps or in the same reaction vessel, orboth. Therefore, a need remains for a process for C—C coupling ofhydrocarbons which can be performed in fewer steps and preferably, inthe same reaction vessel.

SUMMARY OF THE INVENTION

[0015] The present invention provides a process for producing organicsubstituted aromatic compounds (which includes organic substitutedheteroaromatic compounds and biaryl compounds) in a two-step reaction.In the first step, the aromatic compound is borylated in a reactioncomprising a borane or diborane reagent (any boron reagent where theboron reagent contains a B—H, B—B or B—Si bond) and an iridium orrhodium catalytic complex. In the second step, a metal catalystcatalyzes the formation of the organic substituted aromatic compoundfrom the borylated compound and an electrophile such as an aryl ororganic halide, triflate (OSO₂CF₃), or nonaflate (OSO₂C₄F₉). The stepsin the process can be performed in a single reaction vessel or inseparate reaction vessels. The present invention also provides a processfor synthesis of complex polyphenylenes starting from halogenatedaromatic compounds.

[0016] Therefore, the present invention provides a process for producinga substituted aromatic compound, which comprises (a) reacting anaromatic compound selected from the group consisting of an aryl, a sixmembered heteroaromatic compound, and a five membered heteroaromaticcompound with a borane selected from the group consisting of a boranewith a B—H, B—B, and B—Si bond in the presence of a catalyticallyeffective amount of an iridium or rhodium complex with three or moresubstituents, and an organic ligand selected from the group consistingof phosphorus, carbon, nitrogen, oxygen, and sulfur organic ligands toform an aromatic boron compound; and (b) reacting the aromatic boroncompound with an organic compound selected from the group consisting ofhalide, triflate, and nonaflate in the presence of a catalyticallyeffective amount of a metal catalyst wherein the aromatic group of theorganic compound is coupled to the aromatic group of the aromatic boroncompound to produce the substituted aromatic compound.

[0017] The present invention further provides process for producing anorganic substituted aryl or heteroaryl compound, which comprises (a)reacting in a reaction vessel a first aromatic compound selected fromthe group consisting of an aryl, a six membered heteroaromatic compound,and a five membered heteroaromatic compound with a borane selected fromthe group consisting of a borane with a B—H, B—B, and B—Si bond in thepresence of a catalytically effective amount of an iridium or rhodiumcomplex with three or more substituents, and an organic ligand selectedfrom the group consisting of phosphorus, carbon, nitrogen, oxygen, andsulfur organic ligands to form an aromatic boron compound; and (b)reacting the aromatic boron compound formed in the reaction vessel withan organic compound selected from the group consisting of halide,triflate, and nonaflate in the presence of a catalytically effectiveamount of a metal catalyst wherein the aromatic group of the organiccompound is coupled to the aromatic group of the aromatic boron compoundto produce the organic substituted aryl or heteroaryl compound.

[0018] The present invention further provides a process for producing apolyphenylene, which comprises (a) reacting a mixture of aromaticcompounds with one to five halogen groups and a borane in the presenceof a catalytically effective amount of an iridium or rhodium complexwith three or more substituents, and a phosphorus, carbon, nitrogen,oxygen, or sulfur organic ligand to form a mixture of borylated aromaticcompounds; and (b) reacting the mixture of borylated aromatic compoundsin the presence of a catalytically effective amount of a metal catalystwherein the borylated aromatic compounds in the mixture arecross-coupled to produce the polyphenylene.

[0019] The present invention further provides process for producing apolyphenylene, which comprises (a) reacting a mixture of aromaticcompounds and a borane in the presence of a catalytically effectiveamount of an iridium or rhodium complex with three or more substituents,and a phosphorus, carbon, nitrogen, oxygen, or sulfur organic ligand toform a mixture of borylated aromatic compounds; and (b) reacting themixture of borylated aromatic compounds with a mixture of halogenatedaromatic compounds with at least two halogen groups in the presence of acatalytically effective amount of a metal catalyst wherein the borylatedaromatic compounds in the mixture are cross-coupled to the halogenatedaromatic compounds to produce the polyphenylene.

[0020] In a further embodiment of the above processes, the three or moresubstituents excludes hydrogen.

[0021] In a further embodiment of the above processes, the iridiumcomplex is selected from the group consisting of (Cp*)Ir(H)₂(Me₃P),(Cp*)Ir(H)(BPin)(Me₃P), (Cp*)Ir(H)(C₆H₅)(Me₃P), (Ind)Ir(COD),(Ind)Ir(dppe), (MesH)Ir(BPin)(B(OR)₂)₂, ((R₁)₃P)₃Ir(B(OR₂)₂)₃,(R₁)₂P)₂Ir(BPin)₃, (((R₁)₂P)₃Ir((R₂O)₂B)₃)₂, ((R₁)₃P)₄Ir(BPin),((R₁)₃P)₂Ir(BPin)₃, (MesH)Ir(BPin)₃, and (IrCl(COD))₂, (PMe₃)₂IrH₅,((R₁)₃P)₂IrH₅, and ((R)₃P)₂IrH_(x)(B(OR₂)₂)_(5−x) where x is 0-4,wherein Cp* is 1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane,Me is methyl, H is hydrogen, P is phosphorus, Ind is indenyl, COD is1,5-cyclooctadiene, MesH is mesitylene, and wherein R, R₁, and R₂ arehydrogen, linear or branched alkyl containing 1 to 8 carbons, aryl, or acarbon in a cyclic structure.

[0022] In a further embodiment of the above processes, the iridiumcomplex is (Ind)Ir(COD) wherein Ind is indenyl and COD is1,5-cyclooctadiene, (MesH)Ir(BPin)₃ wherein MesH is mesitylene and BPinis pinacolborane, or (IrCl(COD))₂ wherein COD is 1,5-cyclooctadiene.

[0023] In a further embodiment of the above processes, the rhodiumcomplex is selected from the group consisting of (Cp*)Rh(H)₂ (Me₃P),(Cp*)Rh(H)(BPin)(Me₃P), (Cp*)Rh(H)(C₆H₅)(Me₃P), and(Cp*)Rh(hexamethylbenzene), wherein Cp* is1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane, Me is methyl, His hydrogen, and P is phosphorus.

[0024] In a further embodiment of the above processes, the phosphorusorganic ligand is selected from the group consisting of trimethylphosphine (PMe₃), 1,2-bis(dimethylphosphino)ethane (dmpe), and1,2-bis(diphenylphosphino)ethane (dppe).

[0025] In a further embodiment of the above processes, the borane is aborane ester.

[0026] In a further embodiment of the above processes, the borane ispinacolborane. In a further embodiment of the above processes, the metalis palladium.

[0027] In a further embodiment of the above processes, the metalcatalyst complex is selected from Pd(PPh₃)₄, Pd₂(dba)₃/P(^(t)Bu)₃,PdCl₂(dppf), Pd(OAc)₂/PCy₃ wherein P is phosphorus and Ph is phenyl, dbais dibenzylideneacetone, ^(t)Bu is tert-butyl, dppf isdiphenylphosphinoferrocene.

OBJECTS

[0028] It is an object of the present invention to provide a process forproducing organic substituted aryl compounds and polyphenylenes.

[0029] It is a further object of the present invention to provide atwo-step process for producing organic substituted aryl compounds andpolyphenylenes.

[0030] It is a further object of the present invention to provide atwo-step process that can be carried out in a single reaction vessel.

[0031] These and other objects of the present invention will becomeincreasingly apparent with reference to the following drawings andpreferred embodiments.

DETAILED DESCRIPTION OF THE DRAWINGS

[0032]FIG. 1 shows the formulas for precatalysts 1 to 15. CP* is1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane, Me is methyl, His hydrogen, P is phosphorus, Ind is indenyl, COD is 1,5-cyclooctadiene,MesH is mesitylene, and wherein R, R₁, and R₂ are each selected from thegroup consisting of hydrogen, linear or branched alkyl containing 1 to 8carbons, aryl, and a carbon in a cyclic structure.

[0033]FIG. 2 shows the formulas for precatalysts 16 to 27. Y₄, Y₅, andY₆ are each selected from the group consisting of hydrogen, halide,alkyl, aryl, alkoxide (—O(R₁₁)), and amide (—N(R₁₂) (R₁₃)) wherein R₁₁,R₁₂, and R₁₃ are each selected from the group consisting of hydrogen,linear alkyl containing 1 to 8 carbon atoms, branched alkyl containing 1to 8 carbons, and a carbon in a cyclic structure; R₁₄, R₁₅, and R₁₆ areeach selected from the group consisting of hydrogen, linear alkyl,branched alkyl, and a carbon in a cyclic structure; (PY₇P) isR₁₈R₁₉P—Y₇—PR₂₀R₂₁ wherein R₁₈, R₁₉, R₂₀, and R₂₁ are each selected fromthe group consisting of hydrogen, linear alkyl containing 1 to 8 carbonatoms, branched alkyl containing 1 to 8 carbons, and a carbon in acyclic structure, and Y₇ is a chain containing 1 to 12 carbons; (P

P) is of the formula

[0034] wherein R₂₂, R₂₃, R₂₄, R₂₅, R₂₆, R₂₇, R₂₈, and R₂₉ are eachselected from the group consisting of alkyl chains, carbocyclic rings,and aryl groups; and BY is a boron moiety.

[0035]FIG. 3A shows an example of the one vessel C—H activation/crosscoupling reactions as applied to biaryl synthesis.

[0036]FIG. 3B shows an example of the one vessel C—H activation/crosscoupling reactions as applied to polyphenylene synthesis.

[0037]FIG. 4 shows a mechanism for aromatic borylations catalyzed by Irboryl complexes.

DETAILED DESCRIPTION OF THE INVENTION

[0038] All patents, patent applications, provisional patentapplications, government publications, government regulations, andliterature references cited in this specification are herebyincorporated herein by reference in their entirety. In case of conflict,the present description, including definitions, will control.

[0039] For convenience, wherever the term “aromatic” is used alone, itis to be construed to include both aromatic and heteroaromatic compoundsselected from the group consisting of aryl, six membered heteroaromaticcompounds, and five membered heteroaromatic compounds and the whereverthe term “organic substituted aromatic compounds” is used alone, it isto be construed to include both organic substituted aromatic andheteroaromatic compounds and biaryl compounds.

[0040] The present invention provides a process for producing organicsubstituted aromatic and heteroaromatic compounds including biaryl andbiheteroaryl compounds, which comprises in a first step, reacting anaromatic or heteroaromatic compound with a borane or diborane containinga B—H, B—B or B—Si bond, but preferably a borane ester, in the presenceof a catalytically effective amount of an iridium or rhodium complexwith three or more substituents to produce a borylated aromatic orheteroaromatic intermediate; and in a second step, reacting theborylated aromatic or heteroaromatic intermediate with an organicelectrophile such as an aryl halide, triflate (OSO₂CF₃), or nonaflate(OSO₂C₄F₉), or the like, in the presence of a catalytically effectiveamount of a metal catalyst wherein the aryl group of the aryl or organichalide, triflate, or nonaflate is coupled to the aromatic orheteroaromatic group of the borylated compound to produce the organicsubstituted aromatic or heteroaromatic compound, including biaryl.

[0041] The borylation of an aromatic or heteroaromatic substrate and thesubsequent coupling of the borylated aromatic or heteroaromaticintermediate with a second sp²-hybridized halocarbon can be performed ina single reaction vessel as shown in Scheme 1.

[0042] The present invention further provides a process for producing apolyphenylene, which in a first step comprises reacting a mixture ofaromatic compounds with one to five halogen groups and a borane ordiborane containing a B—H, B—B or B—Si bond, but preferably a boraneester, in the presence of a catalytically effective amount of an iridiumor rhodium complex with three or more substituents, to form a mixture ofborylated aromatic intermediates; and in a second step, reacting themixture of borylated aromatic intermediates in the presence of acatalytically effective amount of a metal catalyst wherein the borylatedaromatic intermediates in the mixture are cross-coupled to produce thepolyphenylene. See FIG. 3B for an example of the process. The mixture ofaromatic compounds can contain all of one type of aromatic compound or amixture of different types of aromatic compounds.

[0043] The present invention further provides a process for producing apolyphenylene, which in a first step comprises reacting a mixture ofaromatic compounds and a borane or diborane containing a B—H, B—B orB—Si bond, but preferably a borane ester, in the presence of acatalytically effective amount of an iridium or rhodium complex withthree or more substituents, to form a mixture of borylated aromaticintermediates; and in a second step, reacting the mixture of borylatedaromatic intermediates with a mixture of halogenated aromatics with atleast two halogen groups in the presence of a catalytically effectiveamount of a metal catalyst wherein the borylated aromatic intermediatesin the mixture are cross-coupled to the halogenated aromatic compoundsto produce the polyphenylene. The mixture of aromatic compounds cancontain all of one type of aromatic compound or a mixture of differenttypes of aromatic compounds.

[0044] In Scheme 2, HB(OR)₂ is preferably BPin.

[0045] The preferred catalysts for producing the borylated intermediatesin the first step of the process comprise iridium (Ir) or rhodium (Rh)in a complex with three or more substituents, preferably excludinghydrogen, bonded to the Ir or Rh and preferably, further including aphosphorus organic ligand, which is at least in part bonded to the Ir orRh. The process for forming B—C bonds between boranes and sp²-hybridizedC—H bonds to produce organoboron intermediates such as ring-substitutedarenes (or aryl boronate esters and acids) according is shown in

[0046] The direct route to aromatic or heteroaromatic boronate estersand acids in the first step produces intermediates which are versatiletransfer reagents in the second step of the process of the presentinvention. The boron in these transfer reagents serves as a mask for abroad range of heteroatoms and functional groups during the catalyticcross-coupling reactions of C—B and C—X (X is Cl, Br, I, triflate,nonaflate) groups in the second step to yield new C—C bonds as shown inscheme 4.

[0047] The above two-step process is particularly useful in thepharmaceutical industry for drug manufacturing and for synthesis ofcompounds in drug discovery. Thus, the present invention furtherprovides catalyst kits that can be used for general couplings in drugdiscovery applications.

[0048] Preferably, the B—C bond-forming reaction between a borane and ansp²-hybridized C—H bond to produce a ring substituted arene in the firststep is catalyzed by a catalyst comprising Ir and Rh in a complex withthree or more substituents, preferably excluding hydrogen as asubstituent, bonded to the Ir or Rh and further preferably, an organicligand selected from the group consisting of phosphorus, carbon,nitrogen, oxygen, and sulfur organic ligands. For example, phosphorusorganic ligands, organic amines, imines, nitrogen heterocycles, ethers,and the like. Preferably, the ligand is in a molar ratio between about 1to 3 and 1 to 1, wherein the organic ligand is at least in part bondedto the iridium or rhodium.

[0049] Effective precatalysts for forming the B—C bonds can be groupedinto two families: those that contain cyclopentadienyl (Cp*, C₅R₅wherein R is CH₃) or indenyl (Ind, C₉R₇ wherein R is H) ligands andthose that contain phosphine ligands. Included are compounds thatcontain both the Cp* and the Ind ligands and the phosphine ligands.

[0050] Preferably, the Ir catalytic composition for the first step ofthe process comprises one of the following: (ArH)Ir(BY)₃ wherein ArH isselected from the group consisting of aromatic, heteroaromatic,polyaromatic, and heteropolyaromatic hydrocarbon and wherein BY is aboron moiety; (MesH)Ir(BY)₃ wherein MesH is mesitylene and wherein BY isa boron moiety; (P(Y₄)(Y₅)(Y₆))₃Ir (H)_(n)(BY)_(3−n) wherein Y₄, Y₅, andY₆ are each selected from the group consisting of hydrogen, halide,alkyl, aryl, alkoxide (—O(R₁₁)), and amide (—N(R₁₂) (R₁₃)) wherein R₁₁,R₁₂, and R₁₃ are each selected from the group consisting of hydrogen,linear alkyl containing 1 to 8 carbon atoms, branched alkyl containing 1to 8 carbons, and a carbon in a cyclic structure, wherein n is 0, 1, or2, and wherein BY is a boron moiety; (P(R₁₄) (R₁₅) (R₁₆))₃Ir(H)_(n)(BY)_(3−n) wherein R₁₄, R₁₅, and R₁₆ are each selected from thegroup consisting of hydrogen, linear alkyl, branched alkyl, and a carbonin a cyclic structure, wherein n is 0, 1, or 2, and wherein BY is aboron moiety; (P(Y₄)(Y₅)(Y₆))₃Ir (H) (R₁₃) (BY) wherein Y₄, Y₅, and Y₆are as above, wherein R₁₃ is selected from the group consisting of alinear alkyl containing 1 to 8 carbon atoms, branched alkyl containing 1to 8 carbons, aryl, and a carbon in a cyclic structure, and wherein BYis a boron moiety; (P(R₁₄)(R₁₅)(R₁₆) )₃Ir (H) (R₁₇) (BY) wherein R₁₄,R₁₅, and R₁₆ are as above; R₁₇ is as above, and wherein BY is a boronmoiety; {(PY₇P) Ir(BY)₃}₂ (μ₂-(PY₇P)) (16) wherein BY is a boron moiety,wherein (PY₇P) is R₁₈R₁₉P—Y₇—PR₂₀R₂₁ wherein R₁₈, R₁₉, R₂₀, and R₂₁ areeach selected from the group consisting of hydrogen, linear alkylcontaining 1 to 8 carbon atoms, branched alkyl containing 1 to 8carbons, and a carbon in a cyclic structure, and wherein Y₇ is a chaincontaining 1 to 12 carbons; (PY₇P) (P(Y₄)(Y₅)(Y₆))Ir(BY)₃ (17) whereinBY is a boron moiety, wherein Y₄, Y₅, and Y₆ are as above, and wherein(PY₇P) is as above; (PY₇P) (P(R₁₀)(R₁₁)(R₁₂))Ir(BY)₃ (18) wherein BY isa boron moiety, wherein R₁₄, R₁₅, and R₁₆ are as above, wherein (PY₇P)is as above; {(P

P)Ir(BY)₃}₂(μ₂-(P

P)) (19) wherein BY is a boron moiety and wherein (P

P) is of the formula

[0051] wherein R₂₂, R₂₃, R₂₄, R₂₅, R₂₆, R₂₇, R₂₈, and R₂₉ are eachselected from the group consisting of alkyl chains, carbocyclic rings,and aryl groups; (P

P)(P(Y₄)(Y₅)(Y₆))Ir(BY)₃ (20) wherein BY is a boron moiety, wherein Y₄,Y₅, and Y₆ are as above, and wherein (P

P) is as above; (P

P)(P(R₁₄)(R₁₅)(R₁₆))Ir(BY)₃ (21) wherein BY is a boron moiety, whereinR₁₄, R₁₅, and R₁₆ are as above, and wherein (P

P) is as above; (PY₇P)Ir(BY)₃ (22) wherein BY is a boron moiety, andwherein and (PY₇P) is as above; (P

P)Ir(BY)₃ (23) wherein BY is a boron moiety, and wherein (P

P) is as above; (P(Y₄)(Y₅)(Y₆))₄Ir(BY) wherein Y₄, Y₅, and Y₆ are asabove and BY is a boron moiety; (P(R₁₄) (R₁₅) (R₁₆))₄Ir(BY) wherein R₁₄,R₁₅, and R₁₆ are as above and BY is a boron moiety;(PY₇P)(P(Y₄)(Y₅)(Y₆))₂Ir(BY) (24) wherein BY is a boron moiety, whereinY₄, Y₅, and Y₆ are above, and wherein (PY₇P) is as above; (P

P)(P(Y₄)(Y₅)(Y₆))₂Ir(BY) (25) wherein BY is a boron moiety, wherein Y₄,Y₅, and Y₆ are as above, and wherein (P

P) is as above; (PY₇P)(P(R₁₄)(R₁₅)(R₁₆))₂Ir(BY) (26) wherein BY is aboron moiety, R₁₄, R₁₅, and R₁₇ are as above, and wherein (PY₇P) is asabove; (P

P) (P(R₁₄)(R₁₅)(R₁₆))₂Ir(BY) (27) wherein BY is a boron moiety, whereinR₁₄, R₁₅, and R₁₆ are as above, and wherein (P

P) is as above.

[0052] Examples of catalytic compositions comprising iridium includethose selected from the group consisting of (Cp*)Ir(H)₂(Me₃P) (1),(Cp*)Ir(H)(BPin)(Me₃P) (2), (CP*)Ir(H)(C₆H₅)(Me₃P) (3), (Ind)Ir(COD)(8), (MesH)Ir(BPin)(B(OR)₂) (9), ((R₁)₃P)₃Ir(B(OR₂)₂)₃ (10),(R₁)₂P)₂Ir(BPin)₃ (11), (((R₁)₂P)₃Ir((R₂O)₂B)₃)₂ (12), ((R₁)₃P)₄Ir(BPin)(13), ((R₁)₂P)₂Ir(BPin)₃ (14), (MesH)Ir(BPin)₃ (9 wherein B(OR)₂ isBPin), IrCl(COD) (15) and (IrCl(COD))₂, wherein CP* is1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane, Me is methyl, His hydrogen, P is phosphorus, Ind is indenyl, COD is 1,5-cyclooctadiene,MesH is mesitylene, and wherein R, R₁, and R₂ are each selected from thegroup consisting of hydrogen, linear or branched alkyl containing 1 to 8carbons, aryl, and a carbon in a cyclic structure.

[0053] Preferably, the Rh catalytic composition for the first stepcomprises one of the following: (Cp′) (P(Y₄) (Y₅)(Y₆))Rh(H)_(n)(BY)_(2−n) wherein Y₄, Y₅, and Y₆ are as above, wherein nis 0 or 1, wherein BY is a boron moiety, and wherein Cp′ is of theformula

[0054] wherein R₃₀, R₃₁, R₃₂, R₃₃, and R₃₄ are each selected from thegroup consisting of hydrogen, alkyl chains, carbocyclic rings, and arylgroups; and (Cp′)(P(R₁₄(R₁₅)(R₁₆))Rh(H)_(n)(BY)_(2−n), wherein R₁₄, R₁₅,and R₁₆ are as above; n is 0 or 1, wherein BY is a boron moiety; andwherein Cp′ is as above.

[0055] Examples of catalytic compositions comprising rhodium includethose selected from the group consisting of (Cp*)Rh(H)₂(Me₃P) (4),(Cp*)Rh(H)(BPin)(Me₃P) (5), (CP*)Rh(H)(C₆H₅)(Me₃P) (6), and(Cp*)Rh(hexamethylbenzene) (7), wherein CP* is1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane, Me is methyl, His hydrogen, and P is phosphorus.

[0056] In the above catalytic compositions, preferably the BY boronmoiety selected from the group consisting of

[0057] wherein R₁, R₂, R₃, R₄, R₅, and R₆ are each selected from thegroup consisting of hydrogen, linear alkyl containing 1 to 8 carbonatoms, branched alkyl containing 1 to 8 carbons, and a carbon in acyclic structure. FIGS. 1 and 2 show the structures of precatalysts 1 to15 and 16 to 27, respectively.

[0058] While the precatalysts can under particular reaction conditionscatalyze the borylation of particular ring-substituted arenes, thereactions proceed more efficiently when an organic ligand such asphosphine ligands (phosphorus organic ligands) are included in thereaction mixture. The addition of phosphine ligands to the reactiongenerates active catalysts which can produce ring-substituted areneboranes (aryl boronate esters and acids) with low catalyst loading. Thefact that phosphine-containing species can catalyze borylation isimportant because numerous phosphines are commercially available.Furthermore, the selectivities of the borylation can be altered as afunction of the phosphine ligand that is added. Examples of phosphineligands include, but are not limited to, trimethyl phosphine (PMe₃),1,2-bis(dimethylphosphino)ethane (dmpe),1,2-bis(diphenylphosphino)ethane (dppe), Cy₃P, and Ph₃P.

[0059] For example, precatalyst 8 can be obtained in two high-yieldingsteps from the common iridium starting material, IrCl₃(H₂O)_(x).Precatalyst 9 can be prepared by reacting 8 with approximately 5equivalents of pinacolborane (HBPin) in mesitylene solvent. It wasdiscovered that commercially available precatalyst 15 will also catalyzeborylations. While all of the precatalysts have similar activities formany substrates, borylations of particular arenes exhibit a remarkableprecatalyst dependence.

[0060] In the absence of phosphine ligands, compound 8 catalyzes theborylation of benzene by HBPin, but relatively high catalyst loading andlong reaction times are required to prepare PhBPin in reasonable yields.At temperatures above 80° C., decomposition to Ir metal occurs, whichhalts catalysis. Compound 9 is not effective in catalysis without theaddition of phosphine.

[0061] Addition of phosphine ligands to solutions of compound 8 and 9generates active catalysts for the production of aryl boronic esterswith low catalyst loading as illustrated for the examples in FIG. 1. Thefact that phosphine-containing species can catalyze borylation isimportant because numerous phosphines are commercially available.Consequently, the selectivities can be altered as a function of thephosphine that is added.

[0062] Another virtue of the present invention is that a broad range ofheteroatoms and functional groups are inert under borylation conditionsas shown in Scheme 5.

[0063] Given that Grignard reagents react with several of these groupsand Pd catalyzes the formation of ArBPin from ArBr and HBPin, thefunctional group tolerance for the Ir-catalyzed chemistry is remarkable.Under appropriate conditions, even iodobenzene can be borylated withoutiodide reduction. In this instance, no conversion was observed whenusing precatalyst 8, whereas precatalyst 9 gives the borylated productsin 95% yield as shown in Scheme 6.

[0064] Therefore, the present substrate compatibility, which is alreadyremarkably broad, is expected to expand with further improvements to thepresent invention.

[0065] For monosubstituted arenes, mixtures of meta and para borylatedproducts are obtained. In contrast to the known Rh complexes thatcatalyze aromatic borylation, the meta:para ratio deviates significantlyfrom 2:1. For most substrates, this ratio exceeds 3:1 and data foranisole are shown in Table 1. TABLE 1 Isomer distributions for catalyticborylations of anisole

Entry Catalyst Temp (° C.) Time (h) o:m:p 1 2 mol % 8/2 PMe₃ 150 299:74:17 2 2 mol % 9/2 PMe₃ 150 41 8:75:17 3 2 mol % 8/dppe 150 223:76:21 4 2 mol % 9/dppe 150 51 3:78:20 5 2 mol % 8/dppe 100 22 2:80:186 2 mol % 3/dppe 100 18 2:80:18 7 2 mol % 9 150 3 12:53:36^(a) 8 2 mol %8/PMe₃ 150 29 2:57:40 9 2 mol % 9/PMe₃ 150 40 3:67:30

[0066] It is noteworthy that the para isomer is more favored for entries7 and 8, where the meta:para ratio is significantly less than 2:1. Thesedata show that while there is a steric bias against ortho borylation,the meta:para ratio is sensitive to the type and amount of phosphineligands that are added. For dppe, the activity at 100° C. is relativelyhigh, and the reaction is complete in less time than at 150° C.

[0067] With the exception of F, and amide functional groups in some Rhcatalyzed reactions, borylation at positions that are ortho tofunctional groups are avoided. Thus, 1,3-substituted aromatics can beselectively borylated at the 5′ position. This is the hardest positionto selectively activate by traditional aromatic substitution chemistryand for electron rich arenes, there are no general methods for preparingderivatives from the 1,3-substituted arenes.

[0068] Furthermore, multiple borylation of 1,3-substituted arenes doesnot occur to a significant extent, which means that equimolar quantitiesof borane and arene give aromatic boronic esters in high yield in theabsence of solvent. Substrates that have been successfully converted toboronate esters under these conditions are shown in scheme 7.

[0069] For fluorinated benzenes, the borylation at ortho positionsoccurs readily. Hence, C₆HF₅ and 1,3,5-trifluorobenzene give mono andtriborylated products, respectively, as shown in Scheme 8.

[0070] It is noteworthy that present Rh catalysts are not compatiblewith halide functionalities and substantial quantities of dehalogenatedand diborylated products are observed. We extended the chemistry tofive-membered rings and heterocycles as shown by the borylation of aprotected pyrrole and 2,6-lutidine in Scheme 9.

[0071] The borylation of aromatic and heteroaromatic compounds and thecatalysts suitable for the borylation are disclosed in the commonlyowned U.S. Application, which was filed Jul. 13, 2002, and which claimspriority to U.S. Provisional 60/305,107 filed Jul. 13, 2001.

[0072] In the second step of the process of the present invention, theborylated intermediate is reacted with a halogenated aryl or organic,triflate, or nonaflate compound in the presence of a metal catalystwhich cross-couples the C at the C—B bond and the C at the C-halogenbond to produce the substituted aromatic, heteroaromatic, biaryl, orbiheteroaryl compound. In a preferred embodiment, the metal comprisingthe metal catalyst is palladium. Examples of Pd catalysts which aresuitable for the cross-coupling include, but are not limited to,Pd(PPh3)₄/P(^(t)Bu)₃, PdCl₃(dppf) Pd(OAc)₂/PCy₃ wherein P is phosphorusand Ph is phenyl, dba is dibenzylideneacetone, ^(t)Bu is tert-butyl, anddppf is diphenylphosphinoferrocene.

[0073] The process for making organic substituted aromatic andheteroaromatic compounds, including biaryls and biheteroaryls, avoidsmany of the limitations of the prior art because (1) the borylationreactions can be carried out in neat substrates, thereby avoidingethereal solvents, (2) since the C—H bonds are selectively activated,halogenation of arenes and conversions to Grignard or organolithiumreagents are eliminated, (3) the only byproducts of the borylationreaction are hydrogen, which is easily removed, and the catalyst, whichis present in low concentrations, can be recovered, (4) the process ofthe present invention tolerates a broad range of functional groups, (6)active catalysts are generated from common precursors and selectivitiescan be altered by adding commercially available ligands such as alkylphosphines, (7) particular substitution patterns which are notoriouslydifficult to achieve using prior art aromatic substitution chemistry canbe obtained in one step starting from inexpensive starting materials,and (8) Ir metal is relatively inert, Ir complexes generally have lowtoxicity, and Ir metal recovered from the reactions can be recoveredfrom the reaction waste and recycled. Furthermore, the process can beused to make chiral organic substituted aromatic compounds.

[0074] The following examples are intended to promote a furtherunderstanding of the present invention.

EXAMPLE 1

[0075] The process of the present invention was inspired by Bergman's(Science 223: 902-908 (1984)) and Jones and Feher's (Acc. Chem. Res. 22:91-100 (1989)) fundamental studies of hydrocarbon (R—H, R=alkyl or aryl)activation by Cp*(Me₃)M^(I) intermediates (M═Ir, Rh; Cp* η⁵-C₅Me₅),which produce Cp*(PMe₃)M^(III)(H)(R) where M—H and M—R bonds result fromR—H scission.

[0076] While investigating stoichiometric B—C bond formation inreactions between Cp*(PMe₃)Ir(H)(Ph) and pinacolborane (HBPin), we foundthat substantial quantities of arylboron products were produced fromcatalytic solvent activation. The major metal-containing product in thisreaction, Cp*(PMe₃)Ir(H)(BPin) (2), was a precatalyst for benzeneborylation with an effective turnover number (TON) corresponding to theformation of three molecules of PhBPin per molecule of 2 (Iverson andSmith, III, J. Am. Chem. Soc. 121: 7696-7697 (1999)). Subsequently,Hartwig and co-workers reported alkane and arene borylations utilizingmuch more active Rh precatalysts, such as Cp*Rh(η⁴-C₆Me₆) (7) (Chen etal., Science 287: 1995-1997 (2000)).

[0077] A comparison of precatalysts 2 and 7 in borylations of varioussubstituted arenes revealed that the Ir system was more selectivetowards arene C—H activation (Cho et al., J. Am. Chem. Soc. 122:12868-12869 (2000)). Given the importance of selectivity in chemicalsynthesis, these findings spurred a detailed investigation of theoriginal Ir system. Those results are described herein.

[0078] Compound 2 is stable in benzene solutions after prolongedthermolysis, which eliminates several mechanistic possibilities,including PMe₃ dissociation to generate Cp*Ir(H)(BPin), an analog ofproposed intermediates in the Rh system. However, added PMe₃ stronglyinhibits catalysis where HBPin is present. This indicated that smallquantities of phosphine-Ir^(V) species could be active. SinceCp*IrH_(4−x)(BPin)_(x) species (x=1, 2) form in the thermolysis ofCP*IrH₄ and HBPin (Kawamura and Hartwig, J. Am. Chem. Soc. 123:8422-8423 (2001)), anisole borylations with identical loadings ofCP*IrH₄ and 2 were compared. From this experiment,Cp*IrH_(4−x)(BPin)_(x) intermediates can be eliminated because they arenot kinetically competent for catalysis and the borylationregioselectivities for Cp*IrH₄ and 2 differ substantially. At 150° C.,the following isomer ratios were obtained for anisole borylation with 20mol % precatalyst loadings: Cp*IrH₄, o:m:p=3:49:48; 2 o:m:p=2:79:19.

[0079] Exclusion of a simple phosphine dissociative pathway narrows theplausible catalysts to two choices: (i) Ir phosphine species arisingfrom Cp* loss or (ii) species where both Cp* and PMe₃ have been lost.The latter possibility was intriguing in light of Marder's synthesis of(η⁶-arene)Ir(BCat)₃ complexes (Cat=ortho-catecholate) from (Ind)Ir(COD)(3, Ind η⁵-C₉H₇, COD=1,5-cyclooctadiene) and HBCat in arene solvents(10). Using an analogous route, we prepared (η⁶-mesitylene)Ir(BPin)₃ (9in which B(OR)₂ is BPin) in 19% yield from (Ind)Ir(COD) (8) and HBPin(Compound 9 has been prepared as an analytically pure white solid.Relevant spectroscopic data included ¹H NMR (C₆D₆) δ1.33 (s,36 H,BO₂C₆H₁₂), 2.23 (s, 9H, C₆H₃(CH₃)₃), 5.62 (s, 3H, C₆H₃(CH₃)₃). ¹¹B NMR(C₆D₆) δ 32.5. ¹³C NMR (C₆D₆) δ 19.68, 25.73, 80.95, 96,97, 118.05).Compound 9 reacted with benzene at 150° C. to produce Ir metal and threeequivalents of C₆H₅BPin, but did not catalyze C₆H₅BPin formation frombenzene and HBPin. Thus, it appears that phosphines or related donorligands are required for catalysis.

[0080] Utilizing the lability of the mesitylene ligand in 9, Irphosphine species were generated in situ from 9 and appropriatephosphines and subsequently screened for activity. Borylation using 2mol % 9 and 4 mol % PMe₃ was viable (Table 1, entry 1), and bothcatalytic activity and TONs for benzene borylation increaseddramatically relative to precatalyst 2. Borylation rates wereappreciable when P:Ir<3:1, but decreased dramatically when P:Ir ratioequals or exceeds 3:1. TABLE 1^(a) Arene: Temp Time Yield Ent. Sub.HBPin Prod. Cat. Ligand (° C.) (h) (%)  1 C₆H₆ 16:1 PhBPin (MeSH) Ir(BPin)₃ PMe₃ 150 15 98^(b) (9)  2 C₆H₆ 16:1 PhBPin (Ind)Ir(COD) PMe₃ 15018 88^(b) (8)  3 C₆H₆ 16:1 PhBPin 8 dppe 150 2 95^(b)  4 C₆H₆ 16:1PhBPin 8 dmpe 150 2 84  5 C₆H₆ 16:1 PhBPin 0.02 mol % 8 dmpe 150 6190^(b)  6 C₆H₆ 16:1 PhBPin (IrCl(COD))₂ dmpe 150 8 74^(b)  7

4:1

8 dmpe 150 1 63  8

1:5

8 dmpe 150 62 76  9

4:1

8 dppe 100 3 81 10

1:1.5

8 dppe 100 14 89 11

1:1.5

8 dppe 100 17 92 12^(c)

1:2

8 dppe 100 4 69 13

10:1 — 8 dppe 100 60 — 14

10:1

9 dppe 100 57 77 15^(c)

1:2

8 dppe 100 25 95 16

1:3

8 dmpe 150 95 82

[0081] The low isolated yields of 9 hampered screening efforts andprecluded practical applications despite the dramatic improvement incatalytic activity. Hence, we sought alternative means for generatingactive catalysts. Since NMR spectra indicated quantitative generation of9 from 8, in situ generation of active catalysts by phosphine additionto 8 was examined. Compound 8 was synthesized in 86% yield from indenyllithium and (IrCl(COD))₂ (Merola and Kacmarcik, Organometallics 8:778-784 (1989)). This approach was successful and results for benzeneborylations are shown in Table 1 (entries 2-5). Chelating phosphinessubstantially increased activity and TONs as highlighted for1,2-bis(dimethylphosphino)ethane (dmpe) where the effective TON of 4500(entry 5) represented an improvement of more than 1000-fold overprecatalyst 2. In addition, active catalysts were generated fromcommercially available sources such as (IrCl(COD))₂ (entry 6).

[0082] If the primary active species generated by PMe₃ addition to 8 and9 are identical to those generated from 2, borylations of substitutedbenzenes should exhibit similar regio- and chemoselectivities. Anisoleis a useful substrate for probing regioselectivity and the meta:pararatios determined from borylations by active species generated by PMe₃addition to 8 and 9 are similar to those for 2 (For catalysts generatedfrom 4 mol % PMe₃ and 2 mol % 8 or 9, the following isomer ratios wereobtained for anisole borylation at 150° C.: 8, o:m:p=9:74:17; 9,o:m:p=8:75:17. For 8 and 9, ortho borylation increases slightly, whichcould signify a minor pathway that is not accessible from 2).

[0083] To assess chemoselectivities, the ratios of arene to benzylicactivation in M-xylene were examined. The selectivities of catalystsgenerated from 8 (13:1) and 9 (12:1) were diminished relative to theselectivity of precatalyst 2 (35:1). Nevertheless, the Ir catalysts weremore selective for arene activation than the Rh catalyst, 7, where theselectivity was 7:1 (Cho et al., J. Am. Chem. Soc. 122: 12868-12869(2000)); a Rh catalyst that is highly selective for benzylic borylationhas been recently reported (Shimada et al., Angew. Chem., Int. Ed. 40:2168-2171 (2001)), and the addition of one equivalent of the chelatingphosphine, 1,2-bis(diphenylphosphino)ethane (dppe) per equivalent of 8or 9 generated catalysts where the arene to benzylic selectivitiesexceeded 142:1.

[0084] Dramatic differences in chemoselectivities between Ir and Rhcatalysts were found for halogenated substrates, where the Ir catalystspreferentially activated C—H bonds. A representative procedure forborylation is given for entry 10 of Table 1. Briefly, in a glove boxunder N₂, compound 8 (57 mg, 0.14 mmol) and dppe (54 mg, 0.14 mmol) weredissolved in HBPin (1.30 g. 10.2 mmol). The solution was transferred toa thick-walled air-free flask containing 1,3-dichlorobenzene (1.00 g,6.80 mmol). The clear yellow solution was heated at 100° C. under N₂ andmonitored by GC-FID. After 14 hours, the reaction mixture was pumpeddown to obtain a brown oil, which was vacuum distilled at 93-94° C.(0.03 mmHg). The resulting oil was then dissolved in Et₂O (10 mL) andwashed with water (5×100 mL). After drying over MgSO₄, ether was removedunder high-vacuum to give 1.65 g (89% yield} of colorless1,3,5-C₆H₃Cl₂BPin (mp 36-38° C.: ¹H NMR (500 MHz. CDCl₃) δ 1.32 (s,12H), 7.41 (t, J=2.0 Hz, 1H), 7.63 (d, J=2.0 Hz, 2H). ¹³C NMR (125 MHz,CDCl₃) δ 24.82, 84.49, 131.1, 133.7, 134.7. ¹¹B NMR (CDCl₃) δ 30). Goodyields of mono- or tri-borylated products of 1,3,5-trifluorobenzene wereobtained by adjusting the arene:HBPin ratio (Table 1, entries 7 and 8).In contrast, previous attempts to effect multiple borylations of1,3,5-trifluorobenzene using the Rh catalyst 7 led to increaseddefluorination (Cho et al., J. Am. Chem. Soc. 122: 12868-12869 (2000)).Borylations of aromatics with heavier halogen substituents provided aneven starker contrast between Ir and Rh catalysts. For example, Ircatalyzed borylations of 1,3-dichlorobenzene and 1,3-dibromobenzenegenerate meta functionalized products in high yields (entries 10 and11), while dehalogenation is the dominant pathway in Rh catalyzedreactions. Dechlorination was observed during attempted silylations of1,3-dichlorobenzene using closely related Rh catalysts (Ezbiansky etal., Organometallics 17: 1455-1457 (1998). The finding that aromaticC-halogen bonds survived in the Ir catalyzed reactions contrasted thePd-catalyzed reactions of boranes and aryl bromides where the C—Br bondswere converted to C—B or C—H bonds (Murata, et al., J. Org. Chem. 65:164-168 (2000)). Entry 12 illustrates an extension of meta selectiveborylation to a halogenated heterocycle.

[0085] Since aryl iodides have the weakest carbon-hydrogen bonds, theyare most susceptible towards reductive cleavage by transition metals.Hence, it is not surprising that the Ir catalysts generated from 8 wereineffective in aromatic borylation of iodobenzene (Table I, entry 13).However, iodobenzene and HBPin reacted smoothly to yield a mixture ofC₆H₄I(BPin) isomers when active catalysts were generated from theIr^(III) source, 9, and dppe (entry 14). Thus, Ir catalysts arecompatible with the entire range of aryl halides. Furthermore,functional group tolerance that was previously found in Rh catalyzedborylations extends to Ir catalyzed reactions (viz., ester compatibilityin entry 15) and Ir selectively borylates symmetrical 1,2-substitutedarenes at the 4-position (entry 16).

[0086] The remarkable selectivity of Ir borylation catalysts foraromatic C—H bonds suggested that Ir byproducts might not interfere insubsequent reactions of the arylboron products. Thus, we envisagedone-vessel elaborations of arene C—H bonds where catalytic borylationsare followed by other metal-catalyzed events in a catalytic cascade. Fora Zr/Pd catalyzed route to substituted biphenyls and terphenyls (SeeFrid et al., J. Am. Chem. Soc. 121: 9469-9470 (1999)). To assess thispossibility, the union of catalytic borylations and Miyaura-Suzukicross-couplings for one-vessel biaryl synthesis from C—H and C—Xprecursors was attempted. As shown in FIG. 3A, the biaryl product can beprepared in good yield from the in situ Pd-catalyzed cross-coupling of3-bromotoluene with 1,3,5-C₆H₃Cl2(BPin), generated by Ir-catalyzedborylation of 1,3-dichlorobenzene with HBPin. An interesting extensionof Ir/Pd tandem catalysis highlighting Ir compatibility with halogenatedaromatics is shown in FIG. 3B. The specific target was a hyperbranchedpolyphenylene that Kim and Webster prepared via Pd catalyzed coupling ofthe bromo/boronic acid monomer, 1,3,5-C₆H₃Br₂(B(OH)₂) (Kim and Webster,Macromolec. 25: 5561-5572 (1992)). Using Ir/Pd tandem catalysis,material with nearly identical NMR (¹³C, ¹H) and GPC data was obtainedfrom HBPin and 1,3-dibromobenzene in a one-vessel reaction. For thematerial in FIG. 3B, M_(ω)=6374 and M_(n)=3460 as compared to thepreviously reported values of M_(ω)=5750 and M_(n)=3820 (Kim andWebster, Macromolec. 25: 5561-5572 (1992)).

[0087] From a mechanistic standpoint, catalytic cycles involvingoxidative addition/reductive elimination from Ir^(I/III) and/orIr^(III/V) intermediates are consistent with the results herein. Withinthis context, we considered Ir^(I) and Ir^(III) boryl intermediates tobe the most likely C—H activating species in the Ir^(I/III) andIr^(III/V) cycles, respectively. Hence, the Ir^(I) and Ir^(III) borylcomplexes, Ir(BPin) (PMe₃)₄ and fac-Ir(BPin)₃(PMe₃)₃, were prepared inorder to evaluate their stoichiometric reactions with arenes.

[0088] Compounds Ir(BPin)(PMe₃)₄ and fac-Ir(BPin)₃(PMe₃)₃ have beenfully characterized as shown by the following spectroscopic data:Ir(BPin)(PMe₃)₄, ¹H NMR (C₆D₆, 25° C.) δ 1.24 (s, 12H, BO₂C₆H₁₂), 1.58(b, 36H, PCCH₃)₃). ¹¹B NMR (C₆D₆) δ 38. ³¹P {¹H} NMR (C₆D₆) δ −57.5;fac-Ir(BPin)₃(PMe₃)₃, ¹H NMR (C₆D₆) δ 1.34 (S, 36H, BO₂C₆H₁₂), 1.52 (m,27H, P(CH₃)₃). ¹¹B NMR (C₆D₆) δ 36.0. ³¹P{¹H} NMR (C₆D₆) δ −64. Inreactions with arenes, compounds Ir(BPin)(PMe₃)₄ andfac-Ir(BPin)₃(PMe₃)₃ both reacted cleanly with benzene to produce PhBPinand the corresponding hydride complexes shown below, which wasconsistent with the idea that Ir^(I) or Ir^(III) species can effectarene borylation; however, the arene products from stoichiometricreactions of Ir(BPin)(PMe₃)₄ and fac-Ir(BPin)₃(PMe₃)₃ with iodobenzenediffered substantially.

[0089] Specifically, compound Ir(BPin)(PMe₃)₄ reacted rapidly withiodobenzene at room temperature, but isomers of C₆H₄I(BPin) were notdetected, even after prolonged thermolysis. Conversely, thermolysis offac-Ir(BPin)₃(PMe₃)₃ in iodobenzene produced m- and p-C₆H₄I(BPin) in 54%yield, based on fac-Ir(BPin)₃(PMe₃)₃, in addition to a 45% yield ofPhBPin.

[0090] Since conversion rates in catalytic reactions plummet when P:Irratios equal or exceed 3:1, the observation that Ir(BPin)(PMe₃)₄ andfac-Ir(BPin)₃(PMe₃)₃ were not kinetically competent for catalysis wasexpected. However, this does not exclude the possibility that identicalintermediates are generated in the stoichiometric and catalyticreactions. Instead, generation of appropriate intermediates undercatalytic conditions could simply be more efficient. Nevertheless, thestoichiometric transformations lend credence to either Ir^(I) orIr^(III) species mediating C—H activations under catalytic conditions.The reactions of Ir(BPin)(PMe₃)₄ and fac-Ir(BPin)₃(PMe₃)₃ withiodobenzene have greater mechanistic implications. For example, theabsence of C₆H₄I(BPin) products in thermolysis of Ir(BPin)(PMe₃)₄mirrored the failed attempt to borylate iodobenzene using the Ir^(I)precatalyst 8 (entry 13). The reactivity of fac-Ir(BPin)₃(PMe₃)₃suggests that an Ir^(III) intermediate may activate C—H bonds in thepresence of C—I bonds, but the chemistry of Ir(BPin)(PMe₃)₄ is moreimportant because it essentially excludes the participation of Ir^(I)species in the successful borylation of iodobenzene using the Ir^(III)precatalyst 9 (entry 14).

[0091] Although catalytic processes involving Ir^(I) intermediates havenot been categorically excluded, we presently prefer the simplifiedmechanism involving Ir^(III) and Ir^(V) intermediates in FIG. 4 for thefollowing reasons: (i) the correlations between stoichiometric andcatalytic borylations of iodobenzene by Ir^(I) and Ir^(III) argueagainst an Ir^(I/III) mechanism, (ii) the catalytic inhibition when P:Irratios equal or exceed 3:1 and the slow borylation rates for the18-electron Ir^(III) complex fac-Ir(BPin)₃(PMe₃)₃ are consistent withthe generation of a reactive 16-electron bisphosphine Ir^(III)intermediate from an 18-electron bisphosphine Ir^(V) resting state,(iii) since chelating phosphines generally inhibit phosphinedissociative pathways, the catalytic activity with chelating phosphinessupports the viability of bisphosphine intermediates, and (iv) the18-electron bisphosphine compound, Ir(PMe₃)₂H₅, is an effectiveprecatalyst for borylation. A more definitive characterization of thecatalytic manifold is underway.

[0092] In summary, an investigation of the original Ir catalytic system,whose promising selectivities could not be practically implemented dueto extremely low effective TONs, has produced a family of efficientborylation catalysts with remarkable regio- and chemoselectivities. Inaddition to providing a direct route to aryl and heteroaryl boroncompounds from boranes and arenes, the viability of a tandem catalyticcascade where the first step is an Ir catalyzed aromatic borylation hasbeen demonstrated. We are optimistic that extensions of these findingswill have significant synthetic applications.

EXAMPLE 2

[0093] This example shows a two-step, one-vessel process for synthesisof the biaryl 3,5-bis(trifluoromethyl)biphenyl from1,3-bis(trifluoromethyl)benzene, a borane (HBPin), and iodobenzene. Anarylboronate ester was produced using an Ir catalyst and thearylboronate was subsequently coupled to the iodobenzene using apalladium catalyst.

[0094] In a glove box, HBPin (448 mg, 3.50 mmol) was added to a mixtureof 1,3-bis(trifluoromethyl)benzene (500 mg, 1.34 mmol), (COD)Ir(Indenyl) (19.5 mg, 0.047 mmol), and dppe (18.6 mg, 0.047 mmol) in asmall air-free flask equipped with a stir bar. The flask was then sealedand heated at 100° C. for 16 hours.

[0095] Afterwards, the reaction solution was allowed to cool to roomtemperature and Pd₂(dba)₃ (42.8 mg, 0.047 mmol), P(tBu)₃ (28.3 mg 0.140mmol), iodobenzene (476 mg, 2.24 mmol), K₂PO₄ (744 mg, 3.50 mmol), andDME (10 mL) were added. The mixture was stirred at 80° C. for 3 hours.The 3,5-bis(trifluoromethyl)biphenyl was obtained (68.2% yield) as acolorless oil. The identity of the 3,5-bis(trifluoromethyl)biphenyl wasconfirmed by comparison to the GC retention time and ¹H NMR data to anauthentic sample prepared from 3,5-bis(trifluoromethyl)phenylpinacolborane and iodobenzene. ¹H NMR (CDCl₃, 300 MHz) δ 8.00 (s, 2H),7.93 (s, 1H), 7.85−7.58 (m, 2H), 7.53−7.42 (m, 3H).

EXAMPLE 3

[0096] This example shows a closed system for a two-step, one-vesselprocess for synthesis of a biphenyl from benzene, a borane (HBPin), anda halogenated phenyl (PhI). An arylboronate ester was produced using anIr catalyst and the arylboronate was subsequently coupled to thehalogenated phenyl using a palladium catalyst.

[0097] In a glove box, benzene (437 mg, 5.60 mmol), Ir(COD)(Indenyl)(3.0 mg, 0.0070 mmol), dppe (2.8 mg, 0.0070 mmol), dodecane (internalstandard, 11.5 mg, 0.0675 mmol), and HBPin (45 mg, 0.352 mmol) wereadded to a J. Young tube equipped with a stir bar. The tube was thensealed, removed from the box, and heated at 100° C. for 18 hours. A GCtrace of the reaction mixture revealed PhBPin in 85.7% yield.

[0098] Next, the reaction solution was allowed to cool to roomtemperature and Pd(PPh₃)₄ (8.1 mg, 0.007 mmol), K₃PO₄ (112 mg, 0.528mmol), PhI (72.7 mg, 0.356 mmol) and DME (2 mL) were added. Threefreeze-pump-thaw cycles were performed to remove residual oxygen and thereaction mixture was heated at 80° C. for two days. GC analysis showed81.8% GC-yield of the biphenyl,79.7% GC-conversion of the iodobenzene,and 79.1% conversion of the PhBPin.

EXAMPLE 4

[0099] This example shows an open system for a two-step, one-vesselprocess for synthesis of a biphenyl from benzene, a borane (HBPin), anda halogenated phenyl (PhI). An arylboronate ester was produced using anIr catalyst and the arylboronate was subsequently coupled to thehalogenated phenyl using a palladium catalyst.

[0100] In a glove box, benzene (1.0 mL, 11.2 mmol), Ir(COD) (Indenyl)(3.0 mg, 0.0070 mmol), dppe (2.8 mg, 0.0070 mmol), dodecane (internalstandard, 12.0 mg, 0.07 mmol), and HBPin (45 mg, 0.352 mmol) were addedto a Schlenk tube equipped with a stir bar. The tube was then sealed,removed from the box, and heated at 100° C. for 18 hours with constantstirring.

[0101] Next, the reaction solution was allowed to cool to roomtemperature and Pd(PPh₃)₄ (8.5 mg, 0.0074 mmol), K₃PO₄ (112 mg, 0.528mmol), PhI (74.9 mg, 0.367 mmol) and DME (2 mL) were added. A GC traceof the reaction mixture revealed PhBPin in 78.9% yield. The reactionmixture was then degassed by purging with nitrogen and stirred at 90-95°C. for 16.5 hours. A GC analysis showed a 97.3% yield of the biphenyl,84.1% GC-conversion of the iodobenzene, and 90.7% conversion of thePhBPin.

EXAMPLE 5

[0102] This example shows an open system for a two-step, one-vesselprocess for synthesis of a biaryl from 1,3-dichlorobenzene, a borane(HBPin), and a 3-bromotoluene.

[0103] In a glove box, 1,3-dichlorobenzene, Ir(COD) (Indenyl) (2 mol %),dppe (2 mol %), and HBPin were added to a Schlenk tube equipped with astir bar. The tube was then sealed, removed from the box, and heated at100° C. for 16 hours with constant stirring.

[0104] Next, the reaction solution was allowed to cool to roomtemperature and Pd(PPh₃)₄ (2 mol %), K₃PO₄), 3-bromotoluene and DME (2mL) were added. The reaction mixture was incubated at 80° C. for 17hours. A CG analysis following the reaction showed an 80% yield of thebiaryl from the 1,3-dichlorobenzene.

EXAMPLE 6

[0105] This example shows an open system for a two-step, one-vesselprocess for synthesis of a hyperbranched polyphenylene from1,3-dibromobenzene.

[0106] In a glove box, 1,3-dibromobenzene, Ir(COD)(Indenyl) (2 mol %),dppe (2 mol %), and HBPin were added to a Schlenk tube equipped with astir bar. The tube was then sealed, removed from the box, and heated at100° C. for 16 hours with constant stirring.

[0107] Next, the reaction solution was allowed to cool to roomtemperature and Pd₂(dba)₃ (0.5 mol %), K₃PO₄, 3-bromotoluene, and^(t)Bu₃P, were added. The reaction mixture was incubated for 15 hourswith refluxing xylenes. The hyperbranched polyphenylene was similar tothat obtained by the process of Kim and Webster (Macromolec. 25:5561-5572 (1992).

[0108] While the present invention is described herein with reference toillustrated embodiments, it should be understood that the invention isnot limited hereto. Those having ordinary skill in the art and access tothe teachings herein will recognize additional modifications andembodiments within the scope thereof. Therefore, the present inventionis limited only by the claims attached herein.

We claim:
 1. A process for producing a substituted aromatic compound,which comprises: (a) reacting an aromatic compound selected from thegroup consisting of an aryl, a six membered heteroaromatic compound, anda five membered heteroaromatic compound with a borane selected from thegroup consisting of a borane with a B—H, B—B, and B—Si bond in thepresence of a catalytically effective amount of an iridium or rhodiumcomplex with three or more substituents, and an organic ligand selectedfrom the group consisting of phosphorus, carbon, nitrogen, oxygen, andsulfur organic ligands to form an aromatic boron compound; and (b)reacting the aromatic boron compound with an organic compound selectedfrom the group consisting of halide, triflate, and nonaflate in thepresence of a catalytically effective amount of a metal catalyst whereinthe aromatic group of the organic compound is coupled to the aromaticgroup of the aromatic boron compound to produce the substituted aromaticcompound.
 2. The process of claim 1 wherein the three or moresubstituents excludes hydrogen.
 3. The process of claim 1 wherein theiridium complex is selected from the group consisting of(Cp*)Ir(H)₂(Me₃P), (Cp*)Ir(H)(BPin)(Me₃P), (Cp*)Ir(H)(C₆H₅)(Me₃P),(Ind)Ir(COD), (Ind)Ir(dppe), (MesH)Ir(BPin)(B(OR)₂)₂,((R₁)₃P)₃Ir(B(OR₂)₂)₃, (R₁)₂P)₂Ir(BPin)₃, (((R₁)₂P)₃Ir((R₂O)₂B)₃)₂,((R₁)₃P)₄Ir(BPin), ((R₁)₃P)₂Ir(BPin)₃, (MesH)Ir(BPin)₃, and(IrCl(COD))₂, (PMe₃)₂IrH₅, ((R₁)₃P)₂IrH₅, and((R)₃P)₂IrH_(x)(B(OR₂)₂)_(5−x) where x is 0-4, wherein Cp* is1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane, Me is methyl, His hydrogen, P is phosphorus, Ind is indenyl, COD is 1,5-cyclooctadiene,MesH is mesitylene, and wherein R, R₁, and R₂ are hydrogen, linear orbranched alkyl containing 1 to 8 carbons, aryl, or a carbon in a cyclicstructure.
 4. The process of claim 1 wherein the iridium complex is(Ind)Ir(COD) wherein Ind is indenyl and COD is 1,5-cyclooctadiene. 5.The process of claim 1 wherein the iridium complex is (MesH)Ir(BPin)₃wherein MesH is mesitylene and BPin is pinacolborane.
 6. The process ofclaim 1 wherein the iridium complex is (IrCl(COD))₂ wherein COD is1,5-cyclooctadiene.
 7. The process of claim 1 wherein the rhodiumcomplex is selected from the group consisting of (Cp*)Rh(H)₂(Me₃P),(Cp*)Rh(H)(BPin)(Me₃P), (Cp*)Rh(H)(C₆H₅)(Me₃P), and(Cp*)Rh(hexamethylbenzene), wherein Cp* is1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane, Me is methyl, His hydrogen, and P is phosphorus.
 8. The process of claim 1 or 2 whereinthe phosphorus organic ligand is selected from the group consisting oftrimethyl phosphine (PMe₃), 1,2-bis(dimethylphosphino)ethane (dmpe),Ph₃P, Cy₃P, and 1,2-bis(diphenylphosphino)ethane (dppe).
 9. The processof claim 1 wherein the borane is a borane ester.
 10. The process ofclaim 1 wherein the borane is pinacolborane.
 11. The process of claim 1wherein the metal is palladium.
 12. The process of claim 1 wherein themetal catalyst complex is selected from Pd(PPh₃)₄, Pd₂(dba)₃/P(^(t)Bu)₃,PdCl₂(dppf), and Pd(OAc)₂/Cy₃P wherein P is phosphorus and Ph is phenyl,dba is phenyl, dba is dibenzylideneacetone, ^(t)Bu is tert-butyl, dppfis diphenylphosphinoferrocene.
 13. A process for producing an organicsubstituted aryl or heteroaryl compound, which comprises: (a) reactingin a reaction vessel a first aromatic compound selected from the groupconsisting of an aryl, a six membered heteroaromatic compound, and afive membered heteroaromatic compound with a borane selected from thegroup consisting of a borane with a B—H, B—B, and B—Si bond in thepresence of a catalytically effective amount of an iridium or rhodiumcomplex with three or more substituents, and an organic ligand selectedfrom the group consisting of phosphorus, carbon, nitrogen, oxygen, andsulfur organic ligands to form an aromatic boron compound; and (b)reacting the aromatic boron compound formed in the reaction vessel withan organic compound selected from the group consisting of halide,triflate, and nonaflate in the presence of a catalytically effectiveamount of a metal catalyst wherein the aromatic group of the organiccompound is coupled to the aromatic group of the aromatic boron compoundto produce the organic substituted aryl or heteroaryl compound.
 14. Theprocess of claim 13 wherein the three or more substituents excludeshydrogen.
 15. The process of claim 13 wherein the iridium complex isselected from the group consisting of (Cp*)Ir(H)₂(Me₃P),(Cp*)Ir(H)(BPin)(Me₃P), (Cp*)Ir(H)(C₆H₅)(Me₃P), (Ind)Ir(COD),(Ind)Ir(dppe), (MesH)Ir(BPin)(B(OR)₂), ((R₁)₃P)₃Ir(B(OR₂)₂)₃,(R₁)₃P)₂Ir(BPin)₃, (((R₁)₃P)₃Ir((R₂O)₂B)₃)₂, ((R₁)₃P)₄Ir(BPin),((R₁)₂P)₃Ir(BPin)₃, (MesH)Ir(BPin)₃, (PMe₃)₂IrH₅, ((R₁)₃P)₂IrH₅, and((R₁)₃P)₂IrH_(x)(B(OR₂)₂)_(5−x), where x is 0-4, (IrCl(COD))₂, whereinCp* is 1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane, Me ismethyl, H is hydrogen, P is phosphorus, Ind is indenyl, COD is1,5-cyclooctadiene, MesH is mesitylene, and wherein R, R₁, and R₂ arehydrogen, linear or branched alkyl containing 1 to 8 carbons, aryl, or acarbon in a cyclic structure.
 16. The process of claim 13 wherein theiridium complex is (Ind)Ir(COD) wherein Ind is indenyl and COD is1,5-cyclooctadiene.
 17. The process of claim 13 wherein the iridiumcomplex is (MesH)Ir(BPin)₃ wherein MesH is mesitylene and BPin ispinacolborane.
 18. The process of claim 13 wherein the iridium complexis (IrCl(COD))₂ wherein —COD is 1,5-cyclooctadiene.
 19. The process ofclaim 13 wherein the rhodium complex is selected from the groupconsisting of (Cp*)Rh(H)₂(Me₃P), (Cp*)Rh(H)(BPin)(Me₃P),(Cp*)Rh(H)(C₆H₅)(Me₃P), and (Cp*)Rh(hexamethylbezene), wherein Cp* is1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane, Me is methyl, His hydrogen, and P is phosphorus.
 20. The process of claim 13 whereinthe phosphorus organic ligand is selected from the group consisting oftrimethyl phosphine (PMe₃), 1,2-bis(dimethylphosphino)ethane (dmpe),Ph₃P, Cy₃P, and 1,2-bis(diphenylphosphino)ethane (dppe).
 21. The processof claim 13 wherein the borane is a borane ester.
 22. The process ofclaim 13 wherein the borane is pinacolborane.
 23. The process of claim13 wherein the metal is palladium.
 24. The process of claim 13 whereinthe metal catalyst complex is selected from Pd(PPh₃)₄,Pd₂(dba)₃/P(^(t)Bu)₃, PdCl₂(dppf), and Pd(OAc)₂/PCy₃ wherein P isphosphorus and Ph is phenyl, dba is phenyl, dba is dibenzylideneacetone,^(t)Bu is tert-butyl, dppf is diphenylphosphinoferrocene.
 25. A processfor producing a polyphenylene, which comprises: (a) reacting a mixtureof aromatic compounds with one to five halogen groups and a borane inthe presence of a catalytically effective amount of an iridium orrhodium complex with three or more substituents, and a phosphorus,carbon, nitrogen, oxygen, or sulfur organic ligand to form a mixture ofborylated aromatic compounds; and (b) reacting the mixture of borylatedaromatic compounds in the presence of a catalytically effective amountof a metal catalyst wherein the borylated aromatic compounds in themixture are cross-coupled to produce the polyphenylene.
 26. The processof claim 25 wherein the three or more substituents excludes hydrogen.27. The process of claim 25 wherein the iridium complex is selected fromthe group consisting of (Cp*)Ir(H)₂(Me₃P), (Cp*)Ir(H)(BPin)(Me₃P),(CP*)Ir(H) (C₆H₅)(Me₃P), (Ind)Ir(COD), (Ind)Ir(dppe),(MesH)Ir(BPin)(B(OR)₂), ((R₁)₃P)₃Ir(B(OR₂)₂)₃, (R₁)₂P)₂Ir(BPin)₃,(((R₁)₂P)₃Ir((R₂O)₂B)₃)₂, ((R₁)₃P)₄Ir(BPin), ((R₁)₂P)₂Ir(BPin)₃,(MesH)Ir(BPin)₃, (IrCl(COD))₂, (PMe₃)₂IrH₅, ((R₁)₃P)₂IrH₅,((R₁)₃P)₂IrH_(x)(B(OR₂)₂)_(5−x), where x is 0-4, wherein CP* is1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane, Me is methyl, His hydrogen, P is phosphorus, Ind is indenyl, COD is 1,5-cyclooctadiene,MesH is mesitylene, and wherein R, R₁, and R₂ are hydrogen, linear orbranched alkyl containing 1 to 8 carbons, aryl, or a carbon in a cyclicstructure.
 28. The process of claim 25 wherein the iridium complex is(Ind)Ir(COD) wherein Ind is indenyl and COD is 1,5-cyclooctadiene. 29.The process of claim 25 wherein the iridium complex is (MesH)Ir(BPin)₃wherein MesH is mesitylene and BPin is pinacolborane.
 30. The process ofclaim 25 wherein the iridium complex is (IrCl(COD))₂ wherein COD is1,5-cyclooctadiene.
 31. The process of claim 25 wherein the rhodiumcomplex is selected from the group consisting of (Cp*)Rh(H)₂(Me₃P),(Cp*) Rh(H)(BPin)(Me₃P), (CP*)Rh(H)(C₆H₅)(Me₃P), and(Cp*)Rh(hexamethylbenzene), wherein CP* is1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane, Me is methyl, His hydrogen, and P is phosphorus.
 32. The process of claim 25 whereinthe phosphorus organic ligand is selected from the group consisting oftrimethyl phosphine (PMe₃), 1,2-bis(dimethylphosphino)ethane (dmpe),Ph₃P, Cy₃P, and 1,2-bis(diphenylphosphino)ethane (dppe).
 33. The processof claim 25 wherein the borane is a borane ester.
 34. The process ofclaim 25 wherein the borane is pinacolborane.
 36. The process of claim25 wherein the metal is palladium.
 37. The process of claim 25 whereinthe metal catalyst complex is selected from Pd(PPh₃)₄,Pd₂(dba)₃/P(^(t)Bu)₃, PdCl₂(dppf), and Pd(OAc)₂/Cy₃P wherein P isphosphorus and Ph is phenyl, dba is dibenzylideneacetone, ^(t)Bu istert-butyl, dppf is diphenylphosphinoferrocene.
 38. A process forproducing a polyphenylene, which comprises: (a) reacting a mixture ofaromatic compounds and a borane in the presence of a catalyticallyeffective amount of an iridium or rhodium complex with three or moresubstituents, and a phosphorus, carbon, nitrogen, oxygen, or sulfurorganic ligand to form a mixture of borylated aromatic compounds; and(b) reacting the mixture of borylated aromatic compounds with a mixtureof halogenated aromatic compounds with at least two halogen groups inthe presence of a catalytically effective amount of a metal catalystwherein the borylated aromatic compounds in the mixture arecross-coupled to the halogenated aromatic compounds to produce thepolyphenylene.
 39. The process of claim 38 wherein the three or moresubstituents excludes hydrogen.
 40. The process of claim 38 wherein theiridium complex is selected from the group consisting of(Cp*)Ir(H)₂(Me₃P), (Cp*)Ir(H)(BPin)(Me₃P), (CP*)Ir(H)(C₆H₅)(Me₃P),(Ind)Ir(COD), (Ind)Ir(dppe), (MesH)Ir(BPin)(B(OR)₂),((R₁)₃P)₃Ir(B(OR₂)₂)₃, (R₁)₂P)₂Ir (BPin)₃, (((R₁)₂P)₃Ir((R₂O)₂B)₃)₂,((R₁)₃P)₄Ir(BPin), ((R₁)₂P)₂Ir(BPin)₃, (MesH)Ir(BPin)₃, (IrCl(COD))₂,(PMe₃)₂IrH₅, ((R₁)₃P)₂IrH₅, ((R₁)₃P)₂IrH_(x)(B(OR₂)₂)_(5−x), where x is0-4, wherein CP* is 1,2,3,4,5-methylcyclopentadienyl, BPin ispinacolborane, Me is methyl, H is hydrogen, P is phosphorus, Ind isindenyl, COD is 1,5-cyclooctadiene, MesH is mesitylene, and wherein R,R₁, and R₂ are hydrogen, linear or branched alkyl containing 1 to 8carbons, aryl, or a carbon in a cyclic structure.
 41. The process ofclaim 38 wherein the iridium complex is (Ind)Ir(COD) wherein Ind isindenyl and COD is 1,5-cyclooctadiene.
 42. The process of claim 38wherein the iridium complex is (MesH)Ir(BPin)₃ wherein MesH ismesitylene and BPin is pinacolborane.
 43. The process of claim 38wherein the iridium complex is (IrCl(COD))₂ wherein COD is1,5-cyclooctadiene.
 44. The process of claim 38 wherein the rhodiumcomplex is selected from the group consisting of (Cp*)Rh(H)₂(Me₃P),(Cp*)Rh(H)(BPin)(Me₃P), (CP*)Rh(H)(C₆H₅)(Me₃P), and(Cp*)Rh(hexamethylbenzene), wherein CP* is1,2,3,4,5-methylcyclopentadienyl, BPin is pinacolborane, Me is methyl, His hydrogen, and P is phosphorus.
 45. The process of claim 38 whereinthe phosphorus organic ligand is selected from the group consisting oftrimethyl phosphine (PMe₃), 1,2-bis(dimethylphosphino)ethane (dmpe),Ph₃P, and 1,2-bis(diphenylphosphino)ethane (dppe).
 46. The process ofclaim 38 wherein the borane is a borane ester.
 47. The process of claim38 wherein the borane is pinacolborane.
 48. The process of claim 38wherein the metal is palladium.
 49. The process of claim 38 wherein themetal catalyst complex is selected from Pd(PPh₃)₄, Pd₂(dba)₃/P(^(t)Bu)₃,PdCl₂(dppf), wherein P is phosphorus and Ph is phenyl, dba isdibenzylideneacetone, ^(t)Bu is tert-butyl, dppf isdiphenylphosphinoferrocene.